In recent years, as a fine pattern formation technique that replaces photolithography, a pattern formation technique that uses an imprint method attracts attention. The imprint method is the pattern formation technique in which one-to-one transfer of a fine structure is performed by using a mold member (mold) having a fine uneven structure and transferring the uneven structure to a molded resin. For example, in the imprint method in which a photo-curable resin is used as the molded resin, droplets of the photo-curable resin are supplied to the surface of a transfer substrate, a mold having a desired uneven structure and the transfer substrate are brought close to each other until the distance therebetween becomes a predetermined distance and the uneven structure is thereby filled with the photo-curable resin, light is emitted from the side of the mold in this state and the photo-curable resin is thereby cured, and, thereafter, a pattern structure having an uneven structure (uneven pattern) in which projections and depressions of the mold are inverted is formed by separating the mold from a resin layer. In addition, the transfer substrate is etched by using the pattern structure as an etching resist.
The mold used in the imprint method is manufactured usually by applying an electron beam-sensitive resist to a base for the mold, performing electron beam drawing on the resist to form a resist pattern, and etching the base by using the resist pattern as an etching mask to form an uneven pattern. Unfortunately, electron beam lithography that uses the electron beam drawing requires use of an expensive drawing apparatus and takes a long time to complete the drawing, and hence there has been a problem in that the manufacturing cost of the mold is increased. In addition, when a foreign object enters between the mold and the transfer substrate in the imprint, both of the mold and the transfer substrate are significantly damaged, and it becomes difficult to reuse the damaged mold, and hence there has been a problem in that the expensive mold manufactured by the electron beam lithography is lost.
To cope with this, a mold manufactured by the electron beam lithography is used as a master mold, a duplicate mold (hereinafter referred to as a replica mold) is manufactured from the master mold by the imprint method, and the pattern structure is fabricated on the transfer substrate such as a wafer substrate by the imprint method by using the replica mold.
The electron beam drawing is performed based on design coordinates that are designed in advance in the manufacturing of the master mold by the electron beam lithography described above, and the pattern coordinates in the replica mold manufactured by using the master mold are deviated from the original design coordinates due to an error factor occurring at the time of the imprint. In addition, the pattern coordinates in the pattern structure formed on the transfer substrate such as the wafer substrate by using the replica mold are also deviated from the original design coordinates due to the error factor occurring at the time of the imprint.
In the fabrication of the high-accuracy replica mold by using the master mold and the manufacturing of the high-accuracy pattern structure by using the replica mold, the state of the above deviation is grasped and the deviation is reflected in the original design coordinates, or correction is performed by generating a desired deformation in the mold at the time of the imprint. In addition, as means for grasping the state of the deviation described above, a plurality of measurement marks are provided in the master mold in advance, and the magnitude and the direction of the deviation are detected by measuring the measurement mark formed in the replica mold fabricated by using the master mold (an uneven structure in which projections and depressions of the measurement mark of the master mold are inverted) and measuring the measurement mark formed in the pattern structure fabricated by using the replica mold (an uneven structure in which projections and depressions of the measurement mark of the replica mold are inverted) (PTL 1 and 2).